In wireless networks, after a device operating on a particular network (known as a mobile device or user equipment (UE)) has selected a public land mobile network (PLMN) for mobile communication service, the device periodically monitors the performance of its current serving cell when in idle mode of operation (e.g. when there is no active radio connection with a mobile network). The device in idle mode also regularly verifies if there is a neighbour cell that can provide better service quality while maintaining service continuity for the device. When a better cell is identified, a cell re-selection procedure is typically launched to allow the device to camp on the better suitable cell from its current serving cell.
In wireless networks compliant with Third Generation Partnership Project (3GPP) specifications, a cell re-selection procedure is determined by parameters in system information block (SIB) messages broadcasted by the radio access network (RAN) within each cell. A device performs neighbour cell measurements using one or more of the criteria set in the SIB message. The device launches neighbour cell measurements when one or more certain parameters of the serving cell are below or equal to a predetermined threshold set in the SIB message.
In some existing communication networks, the settings of the idle mode mobility measurement parameter thresholds in the SIB messages are mostly static parameters on a per cell basis, not adapted for optimal cell performance. As a result, the measurement threshold settings in the SIB message may lead to excessive current consumption in a device and significantly shorten the device standby battery life if the threshold is set too high. The consequence of the threshold being set too low could be a decreased average serving cell quality, delayed re-selection to a neighbour cell, and an increased likelihood of the device being unreachable for paging (e.g. device going out of service). In some other existing communication networks, the measurement parameters are unspecified or threshold values not configured, which requires the device to perform mobility measurements all the time during idle mode.
Additionally, a measurement threshold in existing mobile networks is usually manually set by a network operator on a per cell basis. The network operators need to perform time-consuming and costly field tests to adjust and optimize the network measurement parameters. As mobile communication technology evolves, the provision of self-optimizing networks (SON) is becoming a high priority for network operators to derive the optimal performance from the network in an automated and cost-effective manner.
References made herein to “user equipment (UE)”, “communication device” and “mobile device”, “mobile station (MS)”, “portable device”, “user terminal”, “terminal equipment” and the like are references to devices operating in conjunction with existing communication networks, e.g. mobile or cellular networks.